The present invention refers to a manipulator for transferring work pieces, especially between two subsequent molding presses within a molding press line, comprising a moving mechanism for performing three dimensional movements on the path between the two molding presses.
Manipulators are known in a large variety. Some of these manipulators comprise a pivotable manipulator arm with at least two limbs that are connected pivotable around a horizontal axis. By this pivoting or folding movement, the distance from the outer end of the manipulator arm to its support can be shortened or prolonged. Moreover, the height of the outer end of the manipulator arm can be changed by suitable pivoting movements of the two limbs of the arm around their horizontal pivot axis.
When work pieces between two molding presses are transferred, it must be considered that there is not much space between the molding presses, and the space between the upper press tool and the lower press tool of one press is very shallow. For this reason this is a common problem to transfer relatively large work pieces from one molding press into another. If manipulators of the above kind are used for this purpose, comprising foldable arms, the support basis of the adjacent molding presses as well as the support of the manipulator itself obstruct the movement, because the manipulator arm follows a circular arc path during the pivoting movement with its outer end and approaches the basis of the molding presses.
Moreover, another problem is related to the construction of such manipulators, because their movement during the transfer of the work pieces is relatively time consuming and takes much energy.
Apart from the above mentioned manipulators comprising a pivoting arm, there are also so-called linear robots with a relatively simple construction that perform a relatively simple linear transfer movement between the molding presses. However, the known linear robots only comprise very few degrees of freedom in the movement of the work pieces, and so they are not suited for the use in a molding press line. Pivot arm manipulators as well as linear robots both have the common problem that the tool support at the end of the manipulator arm has a construction height that makes the insertion of work pieces in a relatively shallow space within the molding press very difficult.